Re: [SeaBIOS] [PATCH] acpi: hide 64-bit PCI hole for Windows XP

[Michael S. Tsirkin]

On Tue, Jul 30, 2013 at 03:10:02PM +0200, Igor Mammedov wrote:
> On Tue, 30 Jul 2013 14:35:25 +0300
> "Michael S. Tsirkin"  wrote:
> > On Tue, Jul 30, 2013 at 09:00:38AM +0200, Igor Mammedov wrote:
> > > Windows XP (32 and 64 bit) crashes if 64-bit PCI hole is present.
> > > Use _OSI ACPI method to blacklist it and hide 64-bit PCI hole.
> > >
> > > _OSI strings reported by XP are taken from here:
> > > http://msdn.microsoft.com/library/windows/hardware/gg463275
> > >
> > > Signed-off-by: Igor Mammedov
> >
> > Hmm did you test this with other OS-es?
> > OSI matches multiple strings so this will often
> > disable the 64 bit memory for newer windows or e.g.
> > for linux.
> >
> > See e.g.
> > ftp://ftp.suse.com/pub/people/trenn/ACPI_BIOS_on_Linux_guide/acpi_guideline_for_vendors.pdf
>
> according to "3.2 How OSI is implemented on Linux" _OSI is broken on linux,
> but I guess we should accommodate this buggy behavior for compatibility reasons.
>
> _OS could be better way to do it, but I haven't found any MS document
> specifying _OS values for Windows flavors.

Yes but we can work it out.
> So far from testing of Windows OSes only
>  (32|64bit) Windows XP and Windows Server 2003 [R2]
> crash when 64-bit PCI hole is present, the rest installs/boots just fine.

Right. That's why I'm thinking _OS might be better.
> > Could we use _OS instead?
> > That's a single string, so it will only match a specific OS.
> > > src/acpi-dsdt.dsl |   25 +++++++++++++++++++++++++
> > >  1 files changed, 25 insertions(+), 0 deletions(-)
> > >
> > > diff --git a/src/acpi-dsdt.dsl b/src/acpi-dsdt.dsl
> > > index 158f6b4..7b55636 100644
> > > --- a/src/acpi-dsdt.dsl
> > > +++ b/src/acpi-dsdt.dsl
> > > @@ -33,6 +33,31 @@ DefinitionBlock (
> > >
> > > /****************************************************************
> > > OS detection
> > > ****************************************************************/
> > > Scope(_SB) {
> > >    External(\P1V, IntObj)
> > >    Method(_INI) {
> > >        If (CondRefOf (\_OSI, Local0)) {
> > >            /* disable 64-bit PCI window for Windows XP and its variants */
> > >            If (\_OSI ("Windows 2001")) {
> > >                Store (Zero, P1V)
> > >            }
> > >            If (\_OSI ("Windows 2001 SP1")) {
> > >                Store (Zero, P1V)
> > >            }
> > >            If (\_OSI ("Windows 2001 SP2")) {
> > >                Store (Zero, P1V)
> > >            }
> > >        }
> > >    }
> > > }
> > >
> > > +/****************************************************************
> > > PCI Bus definition
> > >
> > > ****************************************************************/